Field of the Invention
The present invention relates to a turbine engine such as an airplane turboprop or turbojet, which engine has at least two successive annular rows of stationary vanes, e.g. formed by the vanes of a nozzle stage arranged at the outlet from a compression stage and by an annular row of casing arms arranged downstream from the nozzle.
Description of the Related Art
In a turbine engine, the nozzle arranged at the outlet from a compressor has an annular row of stationary vanes that, in the prior art, are regularly distributed around the longitudinal axis of the turbine engine.
An annular row of casing arms is arranged downstream from the nozzle, where the casing arms serve to transmit forces between internal and external casings to which they are connected and they extend through the stream of gas flowing from the compressor.
In the prior art, the angular positions of the casing arms relative to the nozzle vanes are not optimized. The wakes formed at the trailing edges of the nozzle vanes interact with the casing arms and generate significant head losses, thereby decreasing the performance of the turbine engine. Furthermore, it is possible to observe pumping phenomena that are initiated at the nozzle.
In order to improve the performance of a turbine engine, it is known to implement aerodynamic coupling between two stator elements or two rotor elements. Application EP-A-2 071 127 in the name of the Applicant describes a method of designing a multistage turbine engine turbine that makes it possible to achieve aerodynamic coupling over all of the sets of rotor vanes or of stator vanes of the turbine.